Left my truck sit for two weeks over the holidays and now it is hard to start... Normally 2-4 tries and a few pumps of the gas... Turns over fine, batteries don't seem to be the problem. When it sat it had 3/4 tank of fuel. I have refueled once after getting back at a 1/4 tank. Once it starts it runs fine and seems to start fine when warm.
It sat in 20-50 degree temps, and is now in the 40's. Been a problem for about 4 days now.

Would it be the fuel filter?

2001 F350 7.3 auto 85,000mi.

 

When you're cranking and it's not starting, do you see white smoke coming from the exhaust?

I think the glow plug relay might be the problem. You can do a quick test by letting it sit overnight, then the next morning turn the key to Run (don't start it), and use a screw driver to jump the two large terminals on the relay for about 15 seconds. Then get back in the truck and start it... if it starts easily like it should, that would indicate you have a bad glow plug relay.

The gpr is located on the passenger side right next to the fuel filter under the Powerstroke plastic cover, and is the rearmost relay (toward the rear of the truck). The one right in front of it is the intake air heater relay.

 

No smoke that I see.

 

You've gotten it to start, though, after 2-4 tries since the problem started?

Still do the gpr test tomorrow morning or the next chance you get when it's a cold start after sitting for a while.

 

You may not see much smoke if the glow plugs are cold, just a very fine wisp of smoke. It may also be condensing against the walls of the exhaust pipe before it gets out the tailpipe.
Ryan is pointing you in the right direction, make sure the glow plugs are recieving power.

 

Damn, Dan .... you're a handsome fella!

 

I was the ugly one of three.

 

I just saw this one in your gallery:



You must've played football.

by moderators.

 

At 5'8" I would have been crushed.
But nobody could catch me in the 100 yard dash. 11.2 in the 7th grade was my best time.